Dissolved Organic Material (DOM) exists in many forms ranging from naturally occurring humic acids to by-products or secretions excreted from organisms. DOM is a highly abundant form of organic matter and represents a major reservoir of reactive carbon. It is also a dynamic substrate which can undergo reactions to become accessible to bacteria, plants, and animals as an energy source or it can photodegrade resulting in the production of volatile compounds that can have adverse effects on organisms and the environment. DOM typically contain chromophores that absorb UV and visible light, hence the term Chromophoric (or colored) Dissolved Organic Materials (CDOM ). CDOM will also fluoresce (hence the term FDOM) after light absorption allowing researchers a way to detect and quantify its abundance in water systems using fluorometry.

Detection of DOM levels in water systems greatly increases the power of monitoring efforts and helps explain events such as a sudden decrease in primary productivity, phytoplankton regime shifts, algal blooms, and changes in an environment.